cyberxn

This is kinda odd to me but when the Car starts up it takes about ...2 minits for it to start to Reg on the Meter, but after its Warmd up 5 or more lights on the Gauge will be lit from the Brightest one on Stoich to somwhere off in Lean,
also If i turn on the headlights A/C or anything Useing Power the Gauge Will Burry itsself in Lean(this happends when you Open a Door)
is there a Regulatid + somwhere i can work with or is it somthing more Bad O2 or somthing?

stevej88na

That's pretty normal for a regular oxygen sensor. They take time to warm up, and once warm, basically say "rich" or "lean" and can't really tell by how much. The way the ECU gets close to stoich is by trying to cross the rich/lean boundary as many times per minute as possible. So what you're seeing, with the LEDs bouncing around, is the ECU in feedback mode doing its thing, bouncing from rich to lean and back very quickly.

snowball

the standard O2 sensor is only an on off switch, it can tell if its lean stoich or rich. thats it.

cyberxn

What about the Light Deal when they come on the Gauge Drops off
I may need to take a Vid to show you

stevej88na

This is probably too theoretical:
I'm picturing an idle that's just a bit too high. When you apply a small electrical load, the idle drops a bit, and maybe that's just enough to get into the idle range of the TPS, telling the ECU to go into idle mode, where it tries to maintain the mixture that you've defined with the variable resistor, which may be lean.

I might recalibrate the TPS and idle speed/idle AFR (links for those here). Does your car raise its idle when you turn on you headlights or a/c (wondering about the BAC system)?

EDIT: What I said doesn't make sense, because the TPS is based on the throttle position, not idle speed.

cyberxn

And the pics
when i turn on the lights. the drop from the Motor is Very Slight Almost unnoticeable

The pics are a tad cruddy... 1.2MP cam blows But you can see what i mean

HAILERS

IF you turn the headlignts on while at idle, the BAC opens more to maintain the idle. BAC opening means MORE AIR.

Turn the A/C on and the BAC reacts PLUS the timing advances

There's two jpg of a Palm connected to a RTEK2.0. The first shows Lead and Trail timing at idle with no a/c on. The second shows the timing at idle and the A/C turned ON.

See the difference b/t the -5 Lead and -20 Trail and then with the A/C ON, the new figures, Lead +14.7 and Trail +4.5.

turbo80cid

Just an observation:

I have my (stock) narrow band O2 hooked up to my Microtech LT-8
And I have the Zeitronix wide band w/LCD display.

After a short drive and the NB O2 gets nice and hot
it reads all most the same as my WB O2.

But it I let the car sit at idle for a little bit the reading gets further and further off.

Just thought I would share that…….why?.....because I’m bored at work today.

stevej88na

Thanks for pointing the timing out HAILERS, I didn't know the ECU advances timing under load like that. Looking at training manual page 4-49, it looks like idle timing changes for a/c, p/s, and certain a/t conditions.

Here's a good collection of oxygen sensor info:
http://www.ronsoft.nl/index.php/153

This is worth a read too:
http://www.ronsoft.nl/index.php/152

cyberxn

Honda CRX's?

SuIcIdeKiNg-

that autometer guage tells you nothing its worthless but it looks kinda cool get a widband if you want to monitor you A/F ratios

88rxn/a

iTrader: (6)

nevermind..sorry!

cyberxn

where can i pick one up from then?

GodSquadMandrake

Your o2 sensor is called narrowband. You need a special wideband o2 sensor to get an accurate display of your A/F ratio. I have an LC1, it's used with Megasquirt. I don't think you can replace your stock o2 sensor with this however because the signal will confuse the ECU.


The o2 sensor has a little air pump in it and sniffs the air. That box interprets the signal and sends it to the ECU thru one of the wires. You can hook it up to a laptop thru the serial cable.

Here's what the software looks like:


The purple line that slants down is the Air/Fuel ratio. 14.7:1 is stoichometric which means it burns all the fuel. 13:1 is slightly rich and gives the most power. The car in this log was tuned for power as you can tell by the graph. You can go up to like 16:1 for greater economy but that is dangerous especially on a rotary.

You can buy a gauge for this o2 sensor which will show you the real air/fuel ratio.

Aaron Cake

iTrader: (1)

Worthless to you maybe, because you don't understand how to read it...

edmcguirk

The stock narrow band O2 sensor is garbage compared to a wideband but that does not mean it is worthless. It is useless for quantitative measurments but it is excellent for a gross display of what the ECU is trying to do at the moment.

I had the exact same problem where the engine goes lean whenever I turned on the headlights. I replaced everything and couldn't fix the problem. During the day it ran fine but at night it didn't. I couldn't even find the problem until the Spring when I could test the car during twilight and noticed that the change happened only when I turned on the headlights.

I am pretty sure that the wiring harness ground on top of the engine (under the manifold) was the problem. I pulled the top of the engine bay apart several times and couldn't fix the problem but when I traced the wiring harness in the manual, that ground is listed as the "emissions ground" (if I remember correctly). It was loose and I am pretty sure the problem has been solved since I cleaned that contact and tightened that bolt. (I haven't driven it much)

The O2 sensor has a 1 volt swing. Any extra resistance in the sensor loop can completely swamp the signal and make the car run dirty and rough.

I think it might be possible to wire a ground to one of the diagnostic connectors on the passenger side of the engine for a temporary fix but I would have to look in the manual again.

ed

cyberxn

LOL

cyberxn

Where is this Evil wire located? i will check it.

But a noise Filter or a regulatid + wouldent help anything?

HAILERS

Actually I discovered the timing advance by accident one day while watching the Palm and having turned on the A/C while doing so. Just recently I read that Training Manual that was posted by the NZCONVERTIBLE, and whoa and behold I read the page you cited. I need to sit down and understand what I read someday instead of browsing the thing.

Anyway, the author of this thread seems clueless about afr and idle/acv/timing/o2 sensors, so I give up on this.

cyberxn

im not clueless, but at this point i know a hell of alot more now then i did
So if anything ive benafittid from it.

edmcguirk

The ground wire is difficult to get at because it is under the intake manifold on the top of the top of the engine behind the solenoids.

It is shown on the Bb circuit diagram in the manual as ground point 24. That ground also comes out on the black wire in the fuel pump bypass connector. I suspect connecting a good ground to the spade in the lower portion of the "T" in the Fuel Pump Bypass connector would make a acceptable temporary fix.

There isn't anyplace to install a noise filter in this circuit. Just making sure that the ground is good is the best you can do.

ed

HAILERS

Yeah. I took a cheap shot at you. Ignore it.

brent clement

The ground wire under the intake is also the ground wire for your injectors, so if it's not good you'll have all kinds of issues.

cyberxn

Dont worrie about it hailers tis all good.

well imma step out for a bit and check it over.
I got it in peaces as it is now, might as well check it out

HAILERS

EDMC wrote *I think it might be possible to wire a ground to one of the diagnostic connectors on the passenger side of the engine for a temporary fix but I would have to look in the manual again.**

What he is talking about is that the ECU is grounded on TOP OF THE REAR ROTOR HOUSING. Now that gnd IS NOT the wire that runs from close to the wiper motor to the rear housing. The gnd he talks about requires removal of the upper intake to see it. It is a ring terminal with two black wires.

What he is suggesting, is, that you find the FUEL PUMP CHECK CONNECTOR. That connector is a two socket connector. It is a YELLOW two socket plug with maybe a black rubber boot around it. It is located NEAR the right front strut tower. It is not tied down to anything but is free floating on the harness.

Once found, look at the two wires on that connector. Find the BLACK wire. THAT wire goes up to the ring terminal that I just mentioned. Now he is suggesting that if you got a piece of wire, say 18-22 gauge wire, and put a spade on one end of that wire and installed that spade iinto the two socket plug where the BLACK wire is, you'd be halfway there. The other end of the wire you'd put a ring terminal on it. The attach THAT end to a bolt on the engine. Your choice of where on the engine.

By doing that, you'd know that the ECU ground is, well grounded to the engine for sure. Then see how the engine reacts to that. It shouldn't take a hour to do that.

IF that fails, I'd recommend finding the boost sensor. PUll its elect plug off. Find the wire that is brown with a black stripe (might be pure black on later cars). Do not mistake this wire for the black wire with a white stripe.

Now solder or otherwise splice a new wire to that wire. PUt a ring terminal on the other end of your new wire. Connect that end to the engine. Try driving again and see if that helps.

The brown/black wire at the boost/pressure sensor is common to ALL the sensors in the engine bay, so what your doing is aiding in the gnd of all those sensors. Mainly the afm gnd.